Double port pressure regulator with floating seat

ABSTRACT

A double port regulator assembly includes a first fluid port and a second fluid port. A fixed valve seat assembly is disposed proximate the first fluid port and a floating valve seat assembly is disposed proximate the second fluid port. A first valve plug cooperates with the fixed valve seat assembly to open and close the first fluid port and a second valve lug cooperates with the floating valve seat assembly to open and close the second fluid port. The floating valve seat assembly includes a floating valve seat that is movable with respect to the fixed valve seat.

BACKGROUND

1. Field of the Disclosure

The disclosure relates generally to double port pressure regulators andmore specifically to double port pressure regulators having a fixed seatand a floating seat.

2. Related Technology

Pressure regulators and pressure regulating valves are used in myriadindustrial and residential applications for controlling the downstreampressure of a fluid. For example, in chemical processing plants or oilrefineries, pressure regulating valves are used to manipulate a flowingfluid to compensate for increases or decreases in demand, or other loaddisturbances, and thus keep the fluid pressure regulated. Similarly,pressure regulating valves may be used in plumbing fixtures to maintaina pre-determined pressure of fluid that automatically adjusts tovariations in demand, such as anti-scald valves in showers or faucets.By controlling downstream pressure, pressure regulating valvescompensate for variations in downstream demand. For example, asdownstream demand increases, pressure regulating valves open to allowmore fluid to flow through the pressure regulating valve, thusmaintaining a relatively constant downstream pressure. On the otherhand, as downstream demand decreases, pressure regulating valves closeto reduce the amount of fluid flowing through the pressure regulatingvalve, again maintaining a relatively constant downstream pressure.

One type of pressure regulating valve is the double port regulator.Double port regulators include a single fluid inlet that branches intotwo fluid exit ports. Each fluid exit port has its own valve plug andvalve seat. Double port regulators have the advantage of providing highflow rates. However, double port regulators suffer from the problems ofrequiring very tight machining tolerances to assure that both seatscompletely simultaneously shut off when the valve is closed.

SUMMARY OF THE DISCLOSURE

According to some aspects, a floating valve seat is included in a doubleport regulator or a double port regulator assembly to improve shutoffcharacteristics and to reduce machining tolerance requirements.

In one exemplary arrangement, a double port assembly includes a firstfluid port and a second fluid port, a valve stem that extends throughboth the first fluid port and the second fluid port, the valve stemincluding a first valve plug and a second valve plug, a first fixedvalve seat assembly proximate the first fluid port, and a secondfloating valve seat assembly proximate the second port.

In another exemplary arrangement, a double port regulator includes avalve body having a fluid inlet and a fluid outlet connected by a fluidpassageway, a first fluid port disposed within the fluid passageway, asecond fluid port disposed within the fluid passageway, a fixed valveseat assembly disposed proximate the first fluid port, a floating valveseat assembly disposed proximate the second fluid port, a first valveplug that cooperates with the first valve seat assembly to open andclose the first fluid port, and a second valve plug that cooperates withthe floating valve seat assembly to open and close the second fluidport.

In accordance with the teachings of the disclosure, any one or more ofthe foregoing aspects and/or exemplary aspects of a double portregulator or a double port regulator assembly may further include anyone or more of the following optional forms.

In some optional forms, a double port assembly or a double portregulator may include a floating seat retainer having a through borethat forms the first fluid port, and a floating seat disposed at leastpartially within the floating seat retainer, the floating seat beingmovable along a longitudinal axis of the floating seat retainer. Otheroptional forms may include a floating seat retainer having an annularshoulder that forms a space between the floating seat retainer and thefloating seat. Yet other optional forms may include a biasing elementdisposed within the space between the floating seat retainer and thefloating seat, in some optional forms the biasing element may be a discspring.

Still other optional forms may include a floating seat retainer having afirst portion having a first inner diameter, a second portion having asecond inner diameter, and a third portion having a third innerdiameter, the first inner diameter being smaller than the second innerdiameter, and the second inner diameter being smaller than the thirdinner diameter. Other optional forms may include a floating seat havinga lower flange that is at least partially disposed within the thirdportion. Yet other optional forms may include a chamfered surface on anouter surface of the lower flange. Still other optional forms mayinclude a chamfered surface proximate a first end of the floating seat.

Yet other optional forms may include a retainer element disposed on thefloating seat retainer, the retainer element limiting longitudinalmovement of the floating valve seat. In some optional forms the retainerelement may be an annular disc. In yet other optional forms, theretainer element may include a base portion connected to a retainingportion by an angled portion. In still other optional forms, theretaining portion may be offset from the floating retainer by atolerance gap. In some optional forms, the tolerance gap is preferablybetween 50% and 75% of the flange height of the floating seat.

BRIEF DESCRIPTION OF THE DRAWINGS

Objects, features, and advantages of the present invention will becomeapparent upon reading the following description in conjunction with thedrawing figures, in which:

FIG. 1 is a cross-sectional view of a double port pressure regulatorhaving a floating seat.

FIG. 2 is a close up cross-sectional view of a double port assembly ofFIG. 1, the double port assembly having a fixed seat, a valve plug, anda floating seat.

DETAILED DESCRIPTION

Certain examples are shown in the above-identified figures and describedin detail below. The figures are not necessarily to scale and certainfeatures and certain views of the figures may be shown exaggerated inscale or in schematic for clarity and/or conciseness. Additionally, anyfeatures from any exemplary embodiment may be included with, areplacement for, or otherwise combined with other features to form otherembodiments.

Turning now to FIG. 1, a double port pressure regulator 10 isillustrated that is constructed in accordance with the teachings of thedisclosure. The double port pressure regulator 10 includes a valve body12 having a fluid inlet 14 and a fluid outlet 16 that are connected by afluid passageway 18. The fluid passageway 18 includes a first fluid port21 and a second fluid port 23, through which fluid may flow from thefluid inlet 14 to the fluid outlet 16. In the embodiment illustrated inFIG. 1, fluid flows from the fluid inlet 16 on the left side of FIG. 1,through the fluid passageway 18, to the fluid outlet 16 on the rightside of FIG. 1. In alternate embodiments, the fluid inlet 14 and thefluid outlet 16 may be reversed.

Fluid flow through the first fluid port 21 and through the second fluidport 23 is controlled by a first valve plug 20, which cooperates with afirst valve seat assembly 22, and a second valve plug 24, whichcooperates with a second valve seat assembly 26. The first valve plug 20and the second valve plug 24 are operatively connected to a valve stem28, which extends through the first fluid port 21 and the second fluidport 23 in the embodiment of FIGS. 1 and 2. However, in alternateembodiments, the valve stem need not extend through the first fluid port21 and the second fluid port 23, but could extend through other portionsof the valve body 12. The first and second fluid ports 21, 23, the valvestem 28, and the first and second valve plugs 20, 24, form a double portassembly 29. An actuator 30 is operatively connected to the valve stem28 to move the first valve plug 20 and the second valve plug 24 relativeto the first valve seat assembly 22 and to the second valve seatassembly 26, respectively.

In a first position, the first valve plug 20 is spaced apart from thefirst valve seat assembly 22, leaving a gap between the first valve plug20 and the first valve seat assembly 22, and the second valve plug 24 isspaced apart from the second valve seat assembly 26, leaving a gapbetween the second valve plug 24 and the second valve seat assembly 26.In the first position, fluid is allowed to flow through the fluidpassageway 18 from the fluid inlet 14 to the fluid outlet 16 through thefirst port 21 and through the second port 23. In other words, in thefirst position, the double port regulator 10 is open.

In a second position, the first valve plug 20 contacts the first valveseat assembly 22 and the second valve plug 24 contacts the second valveseat assembly 26, as illustrated in FIG. 2. In the second position,fluid is restricted from flowing through the fluid passageway 18. Inother words, in the second position, the double port regulator 10 isclosed.

In a third position, which is an intermediate position, the first valveplug 20 is spaced apart from the first valve seat assembly 22, and thesecond valve plug 24 contacts the second valve seat assembly 26, asillustrated in FIG. 1. The intermediate position is reached when thedouble port regulator 10 is in the process of opening (but notcompletely open) or in the process of closing (but not completelyclosed), and fluid flows through the first fluid port 21, but notthrough the second fluid port 23, in the intermediate position.

The actuator 30 positions the first valve plug 20 and the second valveplug 24 to achieve a desired flow rate of fluid through the fluidpassageway 18 by varying the distance between the first valve plug 20and the first valve seat assembly 22, and by varying the distancebetween the second valve plug 24 and the second valve seat assembly 26.By providing for an intermediate position where only one of the valveplugs contacts a valve seat assembly, manufacturing tolerances may bereduced and shutoff metering of fluid may be improved and more preciselycontrolled near the cutoff point.

The actuator 30 includes a biasing element, such as an actuator spring32 that biases a diaphragm 34 towards and/or away from the fluid flowpassageway 18. The diaphragm 34 is operatively connected to a diaphragmplate 36, which is operatively connected, in turn, to the valve stem 28.The actuator spring 32 positions the diaphragm 34, which positions thediaphragm plate 36 and the valve stem 28 to locate the first valve plug20 and to locate the second valve plug 24 as desired to control fluidflow through the fluid passageway 18.

A balance spring 33 may be located on an opposite end of the valve stem28 from the actuator 30. The balance spring 33 generally opposes thebias of the actuator spring 32. The balance spring 33 reducesoscillations of the valve stem 28 when the valve stem 28 is positionedby the actuator 30. The balance spring 33 may be seated against thesecond valve plug 24 at one end and within a recess 35 in an end cap 37.

A guide sheath, such as a cylindrical guide sheath 39, may also beseated within the recess 35 and the balance spring 33 may surround thecylindrical guide sheath 39, at least partially. One end of the valvestem 28 may be seated within the cylindrical guide sheath 39 so that thecylindrical guide sheath 39 maintains proper alignment of the valve stem28 when the valve stem is positioned by the actuator 30.

Turning now to FIG. 2, the first and second valve plugs 20, 24, and thefirst and second valve seat assemblies 22, 26, are illustrated in moredetail. The first seat assembly 22 may be a fixed seat assembly. Inother words, the fixed seat assembly does not move with respect to thevalve body 12. The first seat assembly 22 includes a first or fixed seatretainer 40. The fixed seat retainer 40 includes a through bore 42 thatforms the first fluid port 21. The through bore 42 may include a firstportion 44 that has a first inner diameter, a second portion 46 that hasa second inner diameter, and a third portion 48 that has a third innerdiameter. The first inner diameter may be smaller than the second innerdiameter, which may be smaller than the third inner diameter.

The first portion 44 may include a seating surface 50 that cooperateswith the first valve plug 20 to close or open the first fluid port 21. Afixed seat 52 may be disposed within the second portion 46 to form thefirst portion 44, in one example. In other embodiments, the fixed seat52 may be integrally formed with the fixed seat retainer 40. A fixedseat plug 54 may be disposed at least partially within the fixed seatretainer 40. The fixed seat plug 54 may include an upper flange 56,which fits within the third portion 48 of the fixed seat retainer 40.The fixed seat retainer 40 may include one or more annular channels 58that are sized to retain a seal, such as an o-ring 60. In oneembodiment, the fixed seat plug 54 is operatively connected to the fixedseat retainer 40 by a threaded connection 61. In other embodiments,other connections may be used, such as, for example, welded connections,epoxy connections, interference fit connections, crimped connections,etc.

The second seat assembly 26 may be a floating seat assembly. Thefloating seat assembly may include a valve seat that moves with respectto the valve body 12 or with respect to the first seat assembly 22. Thesecond seat assembly 26 includes a second or floating seat retainer 62.The floating seat retainer 62 includes a through bore 64 that forms thesecond fluid port 23. The through bore 64 may include a first portion 66that has a first inner diameter, a second portion 68 that has a secondinner diameter, and a third portion 70 that has a third inner diameter.The first inner diameter may be smaller than the second inner diameter,which may be smaller than the third inner diameter.

A floating seat 72 may be at least partially disposed within the secondportion 68 and the third portion 70, in one example. The floating seat72 is movable along a longitudinal axis A of the floating seat retainer62. The floating seat 72 may include a seating surface 74 thatcooperates with the second valve plug 24 to close or open the secondfluid port 23. The floating seat 72 may include a lower flange 76 thatfits within the third portion 70 of the floating seat retainer 62. Thefloating seat retainer 62 may include one or more annular channels 78,80 that are sized to retain a seal, such as o-rings 82, 84. The floatingseat 72 may include a first chamfered surface 86 at a first end 87 and asecond chamfered surface 88 in an outer surface 89 of the flange 76. Thechamfered surfaces 86, 88 may improve assembly and prevent metal tometal galling as the floating seat 72 moves within the floating seatretainer 62.

The floating seat retainer 62 may include an annular shoulder 90 thatforms a space 91 between the floating seat retainer 62 and the floatingseat 72. A floating seat biasing element, such as a disc spring 92, isdisposed within the space 91. The disc spring 92 biases the floatingseat 72 away from the fixed seat assembly 22. A retainer element, suchas an annular disc 94 is attached to the floating seat retainer 62proximate the floating seat flange 76. In one embodiment, the annulardisc 94 includes a base portion 95 that is connected to a retainingportion 96 by an angled portion 97. The base portion 95 and theretaining portion 96 may be parallel to one another. The angled portion97 offsets the retaining portion 96 from the floating seat retainer 62,thereby forming a tolerance gap 98. The tolerance gap 98 is preferablybetween 50% and 75%, more preferably 60% and 75%, and even morepreferably about 75% of the height of the lower flange 76. Thesepreferred ranges provide enough rigidity for the annular disc 94 toretain the floating valve seat 72 against pressure loading, whilekeeping the valve seat assembly 26 to a relatively small overall size.

In the first position, the first valve plug 20 is spaced apart from thefixed valve seat 50, and the second valve plug 24 is spaced apart fromthe floating seat 72. As the actuator 30 begins to move the valve stem28 towards the second, closed position, initially, the second valve plug24 will contact the floating valve seat 72, because the floating valveseat 72 is biased downward in FIGS. 1 and 2, towards the second valveplug 24. Thus, the second port 23 is closed before the first port 21 isclosed. After the second valve plug 24 contacts the floating valve seat72, the valve stem 28 continues to move towards the second, closedposition. The actuator 20 overcomes the force provided by the discspring 92 and the floating valve seat 72 is pushed upward in FIGS. 1 and2, towards the fixed valve seat assembly 22. Eventually, the first valveplug 20 contacts the fixed valve seat 50, which prevents furthermovement of the valve stem 28, which is now in the second, closedposition with both the first and second fluid ports 21, 23 being closedto fluid flow.

Although certain double port regulators have been described herein inaccordance with the teachings of the present disclosure, the scope ofcoverage of this patent is not limited thereto. On the contrary, whilethe invention has been shown and described in connection with variouspreferred embodiments, it is apparent that certain changes andmodifications, in addition to those mentioned above, may be made. Thispatent covers all embodiments of the teachings of the disclosure thatfairly fall within the scope of permissible equivalents. Accordingly, itis the intention to protect all variations and modifications that mayoccur to one of ordinary skill in the art.

The invention claimed is:
 1. A double port assembly for a double portregulator, the double port assembly comprising: a first fluid port and asecond fluid port; a valve stem that extends through both the firstfluid port and the second fluid port, the valve stem including a firstvalve plug and a second valve plug; a fixed valve seat assemblyproximate the first fluid port; a floating valve seat assembly proximatethe second port, the floating valve seat assembly including a floatingseat retainer having a through bore that forms the first fluid port anda floating seat disposed at least partially within the floating seatretainer, the floating seat being movable along a longitudinal axis ofthe floating seat retainer; and a rigid retainer element disposed on thefloating seat retainer, the retainer element limiting longitudinalmovement of the floating valve seat, the retainer element being anannular disc including a base portion connected to a retaining portionby an angled portion.
 2. The double port assembly of claim 1, thefloating seat retainer including an annular shoulder that forms a spacebetween the floating seat retainer and the floating seat.
 3. The doubleport assembly of claim 2, further comprising a biasing element disposedwithin the space between the floating seat retainer and the floatingseat.
 4. The double port assembly of claim 3, wherein the biasingelement is a disc spring.
 5. The double port assembly of claim 1, thefloating seat retainer including a first portion having a first innerdiameter, a second portion having a second inner diameter, and a thirdportion having a third inner diameter, the first inner diameter beingsmaller than the second inner diameter, and the second inner diameterbeing smaller than the third inner diameter.
 6. The double port assemblyof claim 5, the floating seat including a lower flange that is at leastpartially disposed within the third portion.
 7. The double port assemblyof claim 6, the floating seat including a chamfered surface on an outersurface of the lower flange.
 8. The double port assembly of claim 1, thefloating seat including a chamfered surface proximate a first end. 9.The double port assembly of claim 1, the retaining portion being offsetfrom the floating retainer by a tolerance gap.
 10. The double portassembly of claim 9, wherein the tolerance gap is between 50% and 75% ofa height of a lower flange of the floating seat.